Hearing the news that welding fumes have been classified as carcinogenic (having the potential to cause cancer) is likely to be quite shocking for all welders. Don’t worry, in this article, we will be answering all the burning questions you have regarding this news including how you can avoid welding fumes and mitigate the risks.
Why have welding fumes now been deemed carcinogenic?
The carcinogenicity of welding fumes was assessed by International Agency for Research on Cancer (IARC) in 1989 and classified as “possibly carcinogenic to humans”, based on “limited evidence in human beings” and “inadequate evidence” in experimental animals.
In March 2017, 17 scientists from ten countries met at the IARC to re-evaluate the carcinogenicity of welding and they found substantial new evidence from observational and experimental studies. In the present evaluation, welding fumes and UV radiation from welding are classified as “carcinogenic to humans”.
Who is affected by the new classification of welding fumes as a carcinogen?
All workers, employers, self-employed, contractors, and any others that carry out welding, including mild steel, are required to ensure effective engineering controls are provided and correctly used to control fume. Welding fume doesn’t just affect the welders themselves, it can also affect anyone that is working nearby. The research by IARC found a trend of various eye-related disorders such as cataracts or keratoconjunctivitis occurring in both welders and nearby workers.
In addition, Arc welding generates UV radiation, a risk factor for the rare cancer melanoma. IARC state in their report “Most case-control studies showed positive associations, with risks of developing ocular melanoma generally increased by between two-fold and ten-fold. Two of three studies that assessed risk by duration of employment as a welder showed positive trends. These studies also showed increased ocular melanoma risk associated with eye burns—a proxy for UV exposure—and one reported a positive exposure-response association for cumulative occupational exposure to artificial UV radiation, including welding.”
Also, most studies reported increased risks of lung cancer in welders or other workers exposed to welding fumes. Asbestos exposure and smoking could not explain the excess risk.
Regularly breathing in welding fume can also lead to pneumonia, occupational asthma, metal fume fever (caused by exposure to specific oxides produced when certain metals are heated, symptoms are similar to that of the flu), irritation of throat and lungs, and temporarily reduced lung function.
After reading through all of those risks, you might be feeling a little concerned, but don’t give up on your welding career just yet because, thankfully, these risks can be mitigated.
What can be done to prevent carcinogenic fumes for welders?
General ventilation alone is not enough, fume extraction and filtration must be put into place to minimise the effects of welding fumes as much as possible. There is currently no known level of safe exposure.
The best way to extract welding fumes and dust is by using Local Exhaust Ventilation (LEV). This video by Health and Safety Executive (HSE) does a great job of explaining what LEV is, its key components, and how the system works to protect health.
HSE’s key messages for buying LEV are:
- Work out which jobs and activities cause exposure.
- Write down what the LEV needs to do – get a reputable supplier to advise you.
- Get the right type of LEV to control exposure.
- Involve your employees in LEV design or selection.
- Make sure the LEV is installed properly and works effectively.
- Make sure the LEV has airflow indicators (or equivalent).
- Make sure the supplier provides a User Manual and Log Book (or equivalents).
HSE’s key messages for using LEV are:
- Manage the checking and maintaining of the LEV system.
- Train employees to use the LEV properly (ask a supplier for help).
- Follow instructions in the User Manual (or equivalent).
- Fill in the Log Book and get repairs done.
- Get the LEV thoroughly examined and tested annually.
- Use the thorough examination report as an ‘audit’ and improve if necessary.
What is the best RPE for welding fumes?
Where engineering controls are not adequate to control all fume exposure, adequate and suitable respiratory protective equipment (RPE) is also required. Adflo systems are available at PWP industrial, including the new Adflo Turbo powered air respirator with self-adjusting breathing tube QRS, airflow indicator, prefilter, spark arrestor, particle filter, standard battery, and a charger that incorporates a Li-ion battery, making the turbo almost 20% lighter in weight.
Adflo™ systems deliver fresh, filtered air to the wearer, with a comfortable lightweight design and long-lasting battery. With the right type of filter, the Adflo respirator effectively protects you against both particles and gases all in one system. An odour filter can even be added to remove unpleasant smells.
In addition, the airflow is always a constant nominal rate of 170 litres per minute, regardless of the battery’s charge or the particle loading of the filter. The lightweight Lithium-ion battery fully charges in 4-5 hours and has an operating time of 7-9 hours. If you need to extend operating time, there is also a heavy-duty battery option available.
What PPE should welders use to prevent exposure to welding fumes?
PWP Industrial can supply Kemper’s high quality mobile welding fume extraction units. There are several models that provide different levels of protection, from a basic unit for occasional use during welding to an advanced unit for heavy use thanks to a high capacity and safe filter change. The best model for you will depend on your application and budget.
These mobile fume extractors are ideal for facilities that require welding fume extraction in multiple locations, including maintenance departments, general fabrication and industrial welding. They’re also the perfect choice for small shops or companies with only a few welding stations.
MIG fume torches are also available at PWP Industrial. These fume extraction MIG torches are the best we’ve seen yet! With models from 300-500amp available, they feature a special extractor nozzle to minimise the shield gas disruption. These torches would be classed as on-tool extraction, a specialised type of local exhaust ventilation.
Full welding helmets paired with 3M’s Adflo powered air purifying respirator system can also be used to further reduce exposure to welding fumes.
Disposable dust masks can offer reasonable protection for short jobs but they must be properly fitted to the person using it. One type of mask does not fit all. This type of RPE is relatively cheap but they are often replaced on a daily basis meaning costs involved in their long-term use may be significant.
You should also reduce the time the welder is forced to breathe the fume directly from the torch. This can be achieved by minimising the amount of work carried out in confined spaces, using turntables or other devices to weld in a position where the fume rises away from the welder’s face and reducing internal welding.
Where are carcinogenic welding fumes most likely to occur?
The IARC found that exposure to all welding fume, including mild steel welding fume, is carcinogenic, although it is generally accepted that stainless steel fume is more hazardous than mild steel fume due to the higher chromium and nickel content.
Whilst TIG and flame welding techniques don’t usually involve putting the consumable directly into the arc, they generate much less visible fume particles. For techniques such as resistance welding and plasma cutting, the health risk from the gases found in the fume becomes as important as the risk from metal particles in the fume.
Welding fume is a complex and varying mixture of airborne particles, vapours and gases which arise from the thermal manipulation of metal materials. The fume particles formed from the vaporisation of molten metal as well as by-product vapours and gases may cause a wide range of adverse health effects.
Welding fume produced by aluminium welding risks exposure to ozone, which can result in streaming eyes, nose and a sore throat. It can also aggravate existing medical conditions such as asthma.
For Arc welding, the visible fume comes mostly from the filler wire when it’s exposed to the electric arc. Many of the common metals used in filler wires are harmful and several have Workplace Exposure Limits.
When should welders be concerned about carcinogenic fumes?
Welders should always be concerned about carcinogenic fumes as there is currently no known level of safe exposure. According to HSE welders should:
- Make sure exposure to any welding fume released is adequately controlled using engineering controls (typically LEV).
- Make sure suitable controls are provided for all welding activities, irrelevant of duration. This includes welding outdoors.
- Where engineering controls alone cannot control exposure, then adequate and suitable RPE should be provided to control risk from any residual fume.
- Make sure all engineering controls are correctly used, suitably maintained and are subject to thorough examination and testing where required.
- Make sure any RPE is subject to an RPE programme. An RPE programme encapsulates all the elements of RPE use that you need to consider to ensure it is effective in protecting the wearer.
A panel of experts from industry, consultancies, academia and the HSE formed a working group to create a web tool on breathefreely.org.uk in order to inform managers and supervisors of welders about the best welding fume controls available to protect their health. You only have to answer 4 simple task-related questions and the tool will produce a guidance sheet with the optimum control solution based on the responses.
How does a welding fume extractor work?
Welding fume extractors come in different forms and work in different ways, the mobile fume extraction units from Kemper extract welding fumes at the source. The welding fume extractor cleans the air of harmful chemicals and particles. The contaminated extracted air is transported to the high capacity filter. Some systems come with disposable filters and some are available with cleanable and reusable filters.
Where to buy welding fume protection supplies?
We will go the extra mile to find the product you want, we can even modify existing products or manufacture a bespoke product to suit your requirements. We also know how important it can be for welding supplies to be delivered quickly, that’s why we offer next day delivery for orders placed before 3:00 pm.
Where to get advice on welding fumes?
We are incredibly passionate about the welding and manufacture industry and we want our customers to achieve success – we see ourselves as success enablers. We have advised global industry leaders on their welding and manufacturing processes and our skilled team has extensive experience in the welding industry. As a result, we are able to offer all-round assistance, advice and after-sales service.
If you need advice on reducing exposure to welding fumes, we’re here to help.
Bio of Author:
This article was written by Richard Fryer, a partner at PWP Industrial with 24 years of experience.
Passionate about supporting the professional welder and a demonstrated history of supplying products to the welding and fabrication industry, Richard is an invaluable asset to PWP Industrial and contributes toward the end goal of providing innovative solutions. Connect with Richard on Linkedin.